This section provides background information related to the present disclosure, which is not necessarily prior art.
Some heating, ventilation, and air cooling (HVAC) assemblies generate a rumble noise from the blower motor when the HVAC assembly is operated in certain modes, such as foot and defrost modes. The rumble noise may be the result of a high amount of back pressure causing some air to exit through a blower inlet when the HVAC assembly is in the foot and defrost modes. In other HVAC modes, such as a face mode, there may be no back pressure, and thus no rumble noise. While current HVAC assemblies are suitable for their intended use, they are subject to improvement. For example, it would be desirable and advantageous to at least: (1) prevent the rumble noise in HVAC modes where the noise occurs (e.g., the defrost and foot modes); and (2) not suppress airflow in HVAC modes where the rumble noise does not occur, such as the face mode. The present teachings provide for these advantages, as well as numerous others.